[PATCH] mtd/nand : set Nand flash page address to FBAR and FPAR correctly

b35362 at freescale.com b35362 at freescale.com
Fri Oct 28 01:40:02 EDT 2011


From: Liu Shuo <b35362 at freescale.com>

If we use the Nand flash chip whose number of pages in a block is greater
than 64(for large page), we must treat the low bit of FBAR as being the
high bit of the page address due to the limitation of FCM, it simply uses
the low 6-bits (for large page) of the combined block/page address as the
FPAR component, rather than considering the actual block size.

Signed-off-by: Liu Shuo <b35362 at freescale.com>
Signed-off-by: Jerry Huang <Chang-Ming.Huang at freescale.com>
Signed-off-by: Tang Yuantian <b29983 at freescale.com>
Signed-off-by: Li Yang <leoli at freescale.com>
---
 drivers/mtd/nand/fsl_elbc_nand.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/fsl_elbc_nand.c b/drivers/mtd/nand/fsl_elbc_nand.c
index 33d8aad..681d8c5 100644
--- a/drivers/mtd/nand/fsl_elbc_nand.c
+++ b/drivers/mtd/nand/fsl_elbc_nand.c
@@ -167,15 +167,22 @@ static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
 
 	elbc_fcm_ctrl->page = page_addr;
 
-	out_be32(&lbc->fbar,
-	         page_addr >> (chip->phys_erase_shift - chip->page_shift));
-
 	if (priv->page_size) {
+		/*
+		 * large page size chip : FPAR[PI] save the lowest 6 bits,
+		 *                        FBAR[BLK] save the other bits.
+		 */
+		out_be32(&lbc->fbar, page_addr >> 6);
 		out_be32(&lbc->fpar,
 		         ((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
 		         (oob ? FPAR_LP_MS : 0) | column);
 		buf_num = (page_addr & 1) << 2;
 	} else {
+		/*
+		 * small page size chip : FPAR[PI] save the lowest 5 bits,
+		 *                        FBAR[BLK] save the other bits.
+		 */
+		out_be32(&lbc->fbar, page_addr >> 5);
 		out_be32(&lbc->fpar,
 		         ((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
 		         (oob ? FPAR_SP_MS : 0) | column);
-- 
1.7.1





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